BOGOTA, Colombia -- The U.S. ambassador to Colombia has recommended suspending funding to this country's most elite air force unit, saying it has been stonewalling an investigation into a bombing four years ago that killed 18 civilians.

Also See: Americans Blamed in Colombia Attack San Francisco Chronicle 6/15/01 Previous LA Times articles on the bombing of Santo Domingo

Ambassador Anne W. Patterson also has pledged to help Colombian investigators in their efforts to track down three U.S. citizens who allegedly participated in the bombing of the tiny village of Santo Domingo in December 1998, U.S. congressional sources said.

The steps signal a U.S. resolve to force the Colombian military to comply with basic human rights norms in exchange for continued American aid in fighting this country's long and bloody internal conflict.

They are also an attempt to bring to a close one of the most notorious cases of alleged human rights abuses involving the Colombian military, which in recent years has dramatically improved its record of repression against civilians suspected of guerrilla activity.

"I am very encouraged that despite the cover-up by some in the Colombian air force, the U.S. ambassador is trying to see justice done in this case," said Sen. Patrick J. Leahy, a Vermont Democrat who has long monitored the case.

In recent communications with congressional and embassy officials, Patterson said she has recommended that the State Department decertify the air force's 1st Air Combat Command, the unit involved in the incident, for the organization's failure to adequately investigate the bombing.

Under the so-called Leahy Amendment, U.S. aid and equipment can flow only to those Colombian military units that have been certified as being free of human rights violations, or who are actively taking steps to bring suspected violators to justice.

The U.S. has contributed nearly $2 billion to Colombia over the last several years to combat drugs and fight rebels who have battled to take over the country for nearly four decades. At least three Colombian army units have been decertified; this would mark the first time the air force has faced such a drastic move.

Patterson's recommendation to remove the certification, which is expected to be adopted by the State Department in the near future, would severely affect the air unit, which accounts for 20% of the air force's combat capabilities and relies on U.S. munitions and training for its operations.

The Santo Domingo incident began when a Colombian helicopter crew belonging to the 1st Air Combat Command dropped a U.S.-made cluster bomb on the town during a military operation against leftist guerrillas hiding in the jungle nearby, according to an investigation by the Colombian inspector general's office.

The Times reported this year that military and court records show that two U.S. companies, Occidental Petroleum and AirScan Inc., helped in the planning and execution of the operation around Santo Domingo, which lies 30 miles south of an oil pipeline operated by Los Angeles-based Occidental.

The Colombian helicopter's crew members have testified that they were acting under guidance from U.S. citizens who were flying a surveillance plane belonging to AirScan, which was patrolling the battlefield.

At the time, AirScan was under contract with the Colombian air force to patrol the pipeline, the subject of frequent rebel attacks.

AirScan has denied any involvement in the operation, and a company official declined to comment Friday. Occidental says it can neither confirm nor deny whether it supplied food, fuel and planning facilities to the military on the day of the bombing.

Patterson's decisions are certain to step up pressure against both the Colombian air force and the U.S. citizens involved in the case. The Coast Guard has opened an investigation into whether one of those citizens, Joe Orta, who was allegedly piloting the AirScan plane, was a military officer on active duty with the U.S. Coast Guard at the time of the incident.

Colombian air force officials did not return calls for comment Friday. Orta did not respond to a message left at his family's home; in the past the family has declined to comment.

Patterson's recommendation comes at a time when the air force has come to play an increasingly important role in the Colombian conflict, which pits leftist rebels against the military and an illegal army of right-wing paramilitary fighters. The air force, and especially the 1st Air Combat Command, has recently increased its missions against the rebels, claiming to have killed as many as 100 at a time in attacks.

As a whole, the air force receives between $30 million and $40 million a year in U.S. aid, although it could not be determined Friday how much of that goes directly to the 1st Air Combat Command, according to Adam Isacson, an expert on the Colombian military with the Center for International Policy, a left-leaning Washington think tank.

"If aid is cut off, it will cripple the air force for a while," Isacson said. "It'd be huge."

There have been two parallel investigations of the incident. Just last month, the Colombian inspector general's office, which acts as a sort of internal affairs office for the government, issued a finding that two of the Colombian air force helicopter crew members deliberately dropped the bomb on the town.

The office sanctioned pilot Capt. Cesar Romero and crewman Hector Mario Hernandez with three-month suspensions from the military, the harshest administrative penalties available under Colombian law. The sentence is subject to appeal.

The Colombian military's investigation into the incident, however, has little to show other than thousands of pages of documents.

Over the years, Colombian air force Gen. Hector Fabio Velasco has emphatically denied air force responsibility in the killings, first suggesting that a guerrilla car bomb planted in the town detonated prematurely.

However, he has repeatedly changed his story. At first he denied that the air force dropped any bombs during the operation, despite an internal report within days of the Dec. 13 incident to the contrary. Later, he insisted that the bomb was dropped at least a kilometer from town.

Finally, when Colombian and FBI forensic tests indicated that pieces of shrapnel found in the bodies of the victims were probably fragments from a U.S.-made cluster bomb, Velasco asserted that the guerrillas had somehow obtained a U.S. cluster bomb and used it in the construction of their car bomb to implicate the air force.

Velasco's strong positions and public statements have put in doubt the integrity of the military investigation, because the judge in the case is a lower-ranking officer.

Nonetheless, Patterson indicated that the U.S. is partly to blame for the slow pace of the investigation, congressional sources said.

Patterson acknowledged to congressional officials that the U.S. Embassy has long misplaced a videotape taken by the AirScan plane on the day of the bombing that contains both video and audio.

The Colombian military has a copy of the videotape, but it lacks audio. The Colombian pilots accused of the bombing have maintained that on the day of the attack, they heard the AirScan pilots warn another Colombian air force helicopter involved in the attack to stop shooting at civilians. They have accused the Colombian military of deliberately erasing the audio portion of the tape to turn them into scapegoats.

The Times asked for a copy of the tape earlier this year, but embassy officials said they did not possess one.

In answering a Freedom of Information Act request, the State Department did not include a copy of the tape among the released documents.

Patterson promised that the embassy would transcribe the tape as part of the ongoing investigation, congressional sources said. She didn't explain how the embassy had misplaced the crucial piece of evidence.

It is not known when the tape was found.

Patterson also told congressional officials that the embassy had located the three men working for AirScan on the day of the bombing and is willing to help transmit any request from the Colombian court system to the U.S. court systems to question the men.

Human rights groups welcomed the United States' newfound commitment to the case.

"This position will give a big push to the investigation," said Tito Gaitan, a lawyer for Minga, a Colombian nonprofit group that has represented the victims in the case. "This is the time to rectify past failures and get to the truth."

Previous articles on the bombing of the Colombian village of Santo Domingo accompany this story on The Times' Web site. Go to www.latimes.com/santodomingo.

Copyright 2002 Los Angeles Times

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